Calpurnia- She teaches them how to live with dignity. She also instills many of the lessons a mother would. She shows them everyday, by example, how silly and illogical prejudice is.
Boo-Boo is a living example of Atticus's teaching about walking in someones's shoes before judging them. They come to see Boo not as a neighbourhood monster but as a guardian angel.
Atticus- There is too much to write about this. Suffice to say that Atticus taught, by example, to stand up for what is right despite overwhelming opposition.
Mrs. Dubose- Even though she was prejudice and cranky, she caught her own demons every day. She resolved to be off morphine before she died. She suffered in relative obscurity but stuck to her guns, so to speak.
Miss. Maudie- A simple and progressive independent Southern woman. She taught Scout, in particular, how to hold her head up high.
Alexandra- Although opinionated and slightly bigoted, Alexandra showed a grace under pressure and did the right thing when needed.